1. Field of the Invention.
The present invention relates to an improved cutting tool and inserts for use in the cutting tool.
The present invention further relates to improved concave corner-rounding end mills which use inserted cutting teeth to form surfaces of convex arcuate profile of substantially uniform radius of curvature.
2. Description of the Related Art.
It is known to cut a convex arcuate profile shape with a milling cutter that carries a plurality of cutting inserts. One such embodiment of this process is commonly referred to as `corner-rounding` and is performed on a variety of materials. In reference to this process, U.S. Pat. No. 4,614,463 discloses a milling cutter using a plurality of removable cutting blades clamped to the cutter body in a self-locating manner, these blades having identical cutting edges containing an arcuate section of concave nature and positioned about the axis of rotation so that each cuts the same convex arcuate profile. Such a design allows for removal of the cutting blades for re-sharpening or replacement, but design of specific embodiments of the tool with respect to cutting profile size are dependent on the size of the cutting blade available. Therefore, two such embodiments with comparatively differing cutting profile sizes may require cutting blades of different size, forcing the use of two separate insert sizes to accommodate the different cutting profiles.
In reference to a related process, U.S. Pat. No. 5,123,786 discloses a milling cutter using a plurality of removable cutting inserts clamped to the cutter body, these inserts staggered about the axis of rotation and cutting profile so that each cuts a portion of a roughly concave arcuate profile shape. The inserts are removable but must be sharpened while clamped in the cutter body due to the compound cutting profile required for the intended applications. Design of specific embodiments of the tool with respect to cutting profile are not limited by the size of any one insert cutting edge, only by quantity, as each insert forms only a portion of the cutting profile. Therefore, two such embodiments with comparatively differing cutting profile sizes may use the same size cutting insert in different quantities, allowing the use of a single insert size which can accommodate varying cutting profiles.